there had to have been millions of Tamagotchi sold in a short amount of time back in the day too. A period of high sales doesn't mean it'll stick. The will is selling great, as it's cheaper than anything out and is SDTV friendly. However, as the price of the 360 and ps3 fall, the Wii will become irrelevant.
Yes the wii has games on the list, but if you take console sales into account, which you even praised, they should have more. The games they do have on the list don't even top the most popular games on a console with less consoles out. The wii sales do not translate to many game sales. That's why 3rd party companies will continue to give the Wii the shovelware treatment.